“Basically because when you turn your computer on, you’re going to see some screens and eventually type your password in, you want to have something you do with the keyboard that is signalling to a very low level of the software—actually hard-coded in the hardware—that it really is bringing in the operating system you expect,” Gates said. “Instead of just a funny piece of software that puts up a screen that looks like your login screen and listens to your password and is able to do that.

“So we could have had a single button, but the guy that wanted to do the IBM keyboard design didn’t want to give us our single button, and so we programmed at a low level... it was a mistake.” Gates also said that it was able to take the IBM character set and do some “interesting things” with it.

Of course, the three-key combination—still a part of Windows through Windows 8—has become part of Windows lore, much in the same way that that the “open Apple” key, for example, was well known among Apple users.

The hour-long interview touched on a number of topics, including Gates’ early days at Microsoft and the Bill and Melinda Gates Foundation, which Gates formed with his wife, Melinda, after stepping down as Microsoft’s chief executive in 2000. Gates has recently appeared more publicly—appearing at a Microsoft academic forum, for example—to answer questions about Google and other topics.

Gates was asked, in retrospect, if he actually needed to drop out of Harvard and form the venture that eventually became Microsoft. Gates responded by noting that at the time, software was something that hardware companies did as an aside, because they were forced to. “In fact, though we felt like we had to do it [launch Microsoft] that day, an extra year or two wouldn’t have made a difference,” Gates said. He also jokingly took credit for persuading Facebook chief executive Mark Zuckerberg to drop out as well.

On never attending classes in his original major, mathematics: “I’m probably not going to be the best at this... so I decided I would be the guy who never attended any class he signed up for. So within my first month, I figured out that was my unique positioning. I hoped that the 80 other people [in his class] wouldn’t steal that positioning. It turned out that no one else imitated me.”

On pulling away from Microsoft: “Certainly in my twenties Microsoft was everything, every minute, every sense of I’m doing good work. I knew everybody’s license plate, I could tell you when they drove into the parking lot, when they left, so it was kinda extreme... You’re going from that to having a wife, having kids, having vacations. That felt really good, really appropriate.”